/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.jena.sparql.function.library;

import org.apache.jena.sparql.engine.binding.Binding;
import org.apache.jena.sparql.expr.E_Call;
import org.apache.jena.sparql.expr.ExprList;
import org.apache.jena.sparql.expr.NodeValue;
import org.apache.jena.sparql.function.Function;
import org.apache.jena.sparql.function.FunctionEnv;
import org.apache.jena.sparql.util.Context;

/**
 * Function that evaluates an expression. To convert errors to true or false, use
 * COALESCE.
 */

public class eval implements Function {
    @Override
    public void build(String uri, ExprList args, Context context) {}

    /** Processes unevaluated arguments */

    @Override
    public NodeValue exec(Binding binding, ExprList args, String uri, FunctionEnv env) {
        E_Call e = new E_Call(args);
        NodeValue nv = e.evalSpecial(binding, env);
        if ( nv != null )
            return nv;
        return e.eval(binding, env);
    }
}
